Various hand held or portable lighting devices, including flashlights, are known in the art. Such lighting devices typically include one or more dry cell batteries having positive and negative electrodes. The batteries are arranged electrically in series or parallel in the battery compartment or a housing. The battery compartment also sometimes functions as the handle for the lighting device, particularly in the case of flashlights where a barrel contains the batteries and is also used to hold the flashlight. An electrical circuit is frequently established from a battery electrode through conductive means which are electrically coupled with an electrode of a light source, such as a lamp bulb or a light emitting diode (“LED”). After passing through the light source, the electric circuit continues through a second electrode of the light source in electrical contact with conductive means, which in turn are in electrical contact with the other electrode of a battery. Typically, the circuit includes a switch to open or close the circuit. Actuation of the switch to close the electrical circuit enables current to pass through the lamp bulb, LED, or other light source—and through the filament, in the case of an incandescent lamp bulb—thereby generating light.
In metal flashlights, it has also been conventional to use the barrel and the tail cap as a portion of the conductive means of the electrical circuit. However, in order to increase corrosion resistance and aesthetics of aluminum flashlights, the head, barrel, and tail cap are usually anodized. As a result, either a skin cut to remove anodizing on the inner mating surfaces of the barrel and the tail cap are required to provide a conductive path between the barrel (and the tail cap) and the other portion(s) of the electrical circuit, or the relevant contacting portions must be masked prior to anodizing so that they are not anodized in the first place. Either approach requires additional manufacturing steps, which in turn increases manufacturing costs. Further, the unprotected portions of aluminum or aluminum alloy are more susceptible to corrosion.
Some flashlights designs have proposed the use of a ball to hold the light source of the flashlight within a ball housing to allow the light source to be adjusted with respect to the principal axis of a reflector. Such flashlights, however, do not provide a configuration that suitably addresses the thermal management issues created by today's high power, high brightness LEDs.
Some advanced portable lighting devices provide multiple functions for different needs. For example, a power saving mode and/or an SOS mode may be implemented in a flashlight or other portable lighting devices in addition to the normal “full power” mode. In such portable lighting devices, the user typically elects the desired mode of operation by manipulation of the main power switch. For example, when the flashlight is in the normal mode or the power save mode of operation, the flashlight may be transitioned to another mode of operation, such as an SOS mode by manipulating the main power switch to momentarily turn off and then turn back on the flashlight.
Typically the functionality of multi-mode portable lighting devices of this sort is provided by a microcontroller, which remains powered by the batteries at all times. As a result, the volatile memory of the microcontroller may be used to store the current mode of the flashlight, and thus determine which mode to transition into in the event that a user enters the proper command signal. However, if the portable lighting device—particularly in the case of larger flashlights—is accidentally hit against, or dropped on, a hard surface, the inertia of the battery or batteries may cause the battery or batteries to disconnect from one of the battery contacts for a short period of time. This disconnection will also cause a power loss to the microcontroller, thereby causing the microcontroller to lose track of the mode the flashlight or other lighting device was in prior to the power loss. As a result, the microcontroller will reset the flashlight or other lighting device to its default mode, which is typically off, rather than automatically returning to the prior mode of operation. Resetting under such circumstances is undesirable and potentially hazardous.
Portable lighting devices that include advanced functionality typically include a printed circuit board with a microcontroller or microprocessor to provide the desired functionality. A need exists, however, for a push button switch assembly that includes an integral circuit board that may be readily employed in a variety of portable lighting devices to provide multiple levels of functionality to the same.
In view of the foregoing, a need exists for an improved portable lighting device that addresses or at least ameliorates one or more of the problems discussed above.